Improvement in blast and cupola furnaces



F. LAWRENCE.`

` Blast'and Cupola Furnaces.

N0.r 142,482. Patented Septe'mberZJSS.

UNITEDl STATES PATENT OFFICE.

vFRANKLIN LAWRENCE, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN BLAST AND CUPOLA FURNACES.

Specification forming part of Letters Patent No. 142,482, datedSeptember 2, 1873; application filed l July 2, 1873.

To'all whom t may concern:

-Be it known that I, FRANKLIN LAWRENCE, of Philadelphia, Pennsylvania,have invented an Improved Cupola or Furnace, of which the following is aspecification:

My invention relates to a mode of increasing the reducing effect of fuelin a cupola or furnace; and consists of improved devices whereby theupper portion of the furnace may be obstructed, so as to reduce theopening for the escape of the products of combustion to about the areaof the blast-openings.

The devices which I employ are illustrated in the accompanying drawing,which represents a vertical section of the upper portion ot' a furnaceor cupola, in which is suspended a disk, A.

The diameter of the disk A is such, compared with that of the interiorofr the upper portionor chimney B of the furnace,that the l annularspace between the two is about equal in area to that of the blast-pipes.When the furnace has to be fed, however, it is necessary that this diskshould be elevated above the feedhole a, and should occupy such aposition as to present the least possible obstruction to the volumes ofsmoke and gases which emanate from the fuel; hence, the disk issnspended to a rod passing through a guide, e, fixed in the chimney, therod being attached to a chain passing over pulleys to any suitableraising and lowering mechanism. 0n raising the disk from the positionshown by dotted lines its flange will catch the outer end of an arm,m,hung to the inside of the chimney,

and on continuing to elevate the disk the arm will be gradually raisedto a horizontal position, and the disk will gradually assume thevertical position shown, so as to presentthe least obstruction to theescaping products of combustion.

After charging, the disk may be lowered, as indicated by dotted lines,and retained in a horizontal position at the desired height, the armfalling with the disk.

I claim as my invention- 1. The disk A, arranged in a furnace, andadjustable, so as to be secured in either a horizontal or a verticalposition, as specified.

2. The combination of the ilanged disk A and its guided rod f withthearm m hung to the interior of the chimney, all substantially as setforth. i

In testimony whereof `I have signed my name to this specification in thepresence of two subscribing witnesses.

FRANKLIN LAWRENCE.

Witnesses:

HUBERT HoWsoN, HARRY SMITH.

